Unless you have some exceptional or high demand skills such as:
programming
3-d/motion graphics
networking
really good MS Office tech support skills
ceo of a bank
translation / interpretation
then the usual path to escape teaching is to study hard, get your Japanese ability up, pass JLPT 2, and constantly be on the lookout for job opportunites and good contacts.
Or you can try to be a recruiter, which is fairly cut-throat and nasty.
Or you can get stumble into some job that doesn't require great Japanese or try to find some foreign companies in Japan to work for. This is entirely possible, and A LOT of people in Japan started out as teachers before moving on to something else, and a lot of other people love the cash and freedom that teaching affords you (which is better than many non-teaching jobs), so don't get discouraged.
And dont study linguistics just to be an English teacher, you really wont need it, even if you go on to teach college in Japan.
joey
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